after new timing belt and head gasket, 205 won't start

Hi there,

well I finally managed to put the new timing belt in and get a new
head gasket and fit it. The good news first: There was no damage done
to the valves, and it appears to be almost impossible that the pistons
ever touch the valves. At the topmost point, the pistons are still
around 8 mm below the top of the engine block and thus also away from
the valves. I guess this is unique to the low-compression motor in the
CTi, don't think you can achieve high compression like in the GTi this
way.

Anyhow, now for the bad After I put the head on, tightened the (new) head screws and fitted
everything again (exhaust, ignition, timing belt ...) and checked and
double checked everything, I put the battery in and tried to start.
The engine turns over, but does not fire. I checked the fuel line,
only to be sprayed with gas, thus, there is enough gasoline and
pressure in front of the injection valves. Spark plugs fire, and are
connected in the right order. Injection valves are connected in right
order, only there seems no fuel is injected in the cylinders, since
the sparkplugs stay dry after some attempts to start.

How can I check whether there is an electric signal to the injection
valves? I have a multimeter and an oscilloscope at hand, my question
is, what the normal signal would look like (voltage, duration). And,
if there is no signal, like I am afraid there isn't, what parts could
I check? Are there any connectors that have to be connected or else
the ECU refuses fuel? Meanwhile I triple-checked the connectors all
over, didn't find one that appears not to be connected properly.
My first guess was the lambda probe that might have become
disconnected during the process, but the connectors are fine.

Questions over questions, in short:
WHY DOESN'T THE F* CAR START?

Bye,

Norman

 

Nope, AFAIK the1.9 GTi has the same head as the CTi. The valves can't touch
the pistons there, either, although I thought the got a lot closer than 8mm.
The 1.9 has a longer stroke than the 1.6. The CTi's head might be different
to the 1.6 GTi though.

[SNIP]

I checked my injectors by pulling them out, turning the ignition over and
seeing if they sprayed petrol into a can. Seemed quite conclusive, but don't
have any sources of ignition close by!
I assume you put the timing belt on correctly (with the engine at TDC)?

Chris.

 

Is it not possible that, because you disconnected the battery, the ECU is
out of order and must be resetted? (turning on the contactkey for abt 10
seconds without starting) My two cents...

 

If I had known ... I would not have taken the head off in the first
place.
How does the GTi achieve the higher compression then? Different
camshaft?

I usually smoke while working on fuel systems

Secured crank- and camshaft (TDC of cylinder 1), put belt on, turned
engine over manually several times and checked again that crank- and
camshaft were still in synchronized position. So I am quite sure, it
is on right.

Bye

Norman

 

Right, I wasn't totally up to spec on the CTi - just checked it. I assume
you're talking about the 1.9 CTi compared to the 1.9 GTi? Indeed, the
compression ratio is higher on the GTi. I admit it, the cylinder heads
probably aren't the same. As I said in my previous post, I didn't think the
GTi had 8mm clearance between the valves and the engine block. If I recall
correctly, the valves have less than 1mm clearance, so I assume that the GTi
head just has a lot more skimmed off it, but still enough left to ensure
that the valves and pistons cannot normally touch if the belt fails.

Do you know what injection system your car has? The only specs I found
suggest it's the L-jetronic, but I know early 90's-onwards XU engines had
Motronic injection. L-Jetronic is very simple and there's not much to
connect up, but just double-check all the various sensors are connected up.
Can't really think of much else at the moment, check to see if your
injectors are spraying petrol out, if so then that's a bit odd.

Chris.

 

In the CTi, at least in mine, the pistons do not go up to reach the
edge of the block. There is a around 8 mm wide strip of carbon residue
on the liners in each cylinder, and if I turn the crank, pistons never
reach above this line. So there might also be a different crankshaft
involved? Anyhow, the GTi also has a different ECU (Motronic, opposed
to the L-Jetronic), so it won't be anything like a simple conversion.

This is really good to know. The car I drove before (Ford) was not
fool-proof in this way and a snapping belt gave me a 2000 EUR repair
(took it to the garage, since it was mom's car, also the belt-change
was done at the same garage, still their warranty did not cover things
like a snapping belt).

It's the LU-Jetronic (one with lambda-probe and cat).

Will do that first thing tomorrow. I checked all the connectors I
found, took them apart again and put contact spray on them, put them
back together, to no avail.

I also tried resetting the ECU, but I recall a procedure a little more
complex than let it sit with ignition on for 10 sec, shut it off and
then start?

One odd thing that happened was that the fuel pump kept running for a
long time after I tried to start, actually, it would not turn off for
30 min after I shut the ignition off. Only when I disconnected the
battery it would cease pumping. I removed the Jetronic box, took the
relais for the fuel pump out, disconnected it, reconnected it, and
function is back to normal.

Thanks for your answers! I am a bit clueless right now since I
expected the car would maybe run a little rough at first and I needed
to fine tune things like air-intake, idle and such, but I was pretty
sure that it WOULD RUN.

Bye

Norman

 

Hmm.. I can't quite remember how far up the block the pistons go on the GTi
engine. Now *I'm* thinking about where the extra compression comes from!
Not quite sure about the ECU - 205 GTi's that I've seen have the L-Jetronic
(or LU) - 405's have the Motronic. But, as I said, there's some
inconsistency as from the early 90's onwards, it seems like Peugeot
half-switched to Motronic.

Yeah! It's surprising more cars aren't bullet-proof in this way.

Hmm, check your lambda connection I guess, although I wouldn't expect it to
stop firing if this wasn't attached?! Not had much experience with the
Lambda probe though...

I know people say 'reset the ECU', but seriously, with the LU-Jetronic,
there's so little for the ECU to do I don't really see it as an issue. It
basically just contains a fuel map, I don't think there's anything to really
'reset'. The Motronic has an anti-knock system which 'learns' your
engine/fuel characteristics, but the LU-Jetronic isn't nearly as
sophisticated. It should just pump the fuel (IMO).

That is a bit odd. Sounds like the ECU got stuck. Going back to my point
above about the ECU being pretty simple, I hope it hasn't got fried somehow.
I can imagine the system locking up - obviously I got stuck with the fuel
pump relay engaged - if the ECU fried at this point, disconnecting it would
obviously initially solve the problem, but it might never work again
afterwards. Do you think there's any way you could have damaged the ECU?

No problem. I'll think about it. If you run out of things to check, I'd
consider trying to test it with a different ECU. You could probably grab one
out of a breaker's yard easy enough.

Chris.

 

I know nothing about your engine setup, but I have had this sort of prob on
a Volvo where the distributor was set up 180 degrees out, ie put back on
back to front. I don't know if you've had the dist out to do your job eg is
it run from the back of the cam or on it's own drive. Just a thought.

Stuart

 

I am pretty sure the distributor is set up the right way, the cables
only fit in one direction (ie. facing backwards). It is driven by the
camshaft, so I had to take the cap off to remove the cylinder head.

Could it be that the injection valves got stuck somehow when taking
the head out and moving it around? I could imagine if they are
ball-valves that the balls were misplaced by gravity and now refuse to
open the valve. Are there ballsinvolved, or is it a different
mechanism?

Bye

Norman

 

The camshaft in an engine opens (and in some cases, closes) the valves
- it has no bearing on what the compression ratio of the engine is.


--
Cheers

Peter

Remove the INVALID to reply

 

Could it be that the injection valves got stuck somehow when taking

Cant you just take one out and turn the car over to see if it sprays? and
take a meter and measure between earth and the injector cable so you can see
if its getting a signal or spraying?

J

 

OK.

I took the injection system out and checked if the valves would spray
petrol all over when I tried to start. They didn't, what I somewhat
expected. Pressure in the fuel-pipe is sufficient, though. So I
cornered the problem to why the injection-valves do not let petrol
pass through?
Some petrol that 'accidentally' got into the air-intake made the
engine fire up and turn over a bit, but was soon used up, so I
suppose, the ignition works properly and so do the valves.

By the way, I took the jetronic unit out and opened the box up, it
does not appear to have been 'fried', ie I can't detect any obvious
damage to the electronics.

Right now, I am breeding over the electronics scheme of the 205 with
L-Jetronic to see if there are some connectors I didn't check yet.

Still clueless.

Need the car next week to go and buy dogfood ... a starving dog is no
fun to have at home.

Bye

Norman

 

OK.

Thanks all for your help. The problem was so much simpler then we all
thought.

I lost the mass-connectors for the ECU when putting the head back on.
They vanished in between some cables and hoses and stuff, and I
finally found them, when I was for the fourth time checking for loose
connectors.

I connected them up, and still after all the messing around with it,
the engine would start immediately.

It runs. Great!

Only problem appears to be the relais of the fuel pump has taken some
harm, for the pump keeps running after the ignition is off. Guess I
have to pick up a new one when I run across it, meanwhile bashing the
relais slightly cures it.

Now I have to continue filling up the cooling system, tighten all the
screws and bolts one more time and then go for a test drive.

Good thing. No starving dog!

Bye

Norman